This invention relates to an apparatus and method for inverting a chassis of a mobile vehicle to facilitate the assembly of components on the underside of the vehicle. This would include the installation of vehicle suspensions and axles and related components. The invention has applicability in the assembly of medium and heavy-duty trucks in addition to other mobile vehicles to which components are installed on the underside of the chassis.
Assembly of mobile vehicles sometimes requires installation of components on the underside of or underneath the vehicle chassis. Some components that are installed on the underside of chassis include vehicle suspension systems, axles and accompanying components, such as brakes, wheels, and sometimes drive train components. One conventional method of installation of these underside components involves assembling these components from underneath. This is cumbersome especially for large vehicle chassis. Another method involves hoisting the chassis in the air and then inverting from above while in the air. The chassis is then lowered, components installed. In some cases, the chassis is re-inverted following the installation. There are always safety concerns lifting vehicles weighing thousands of pounds in the air and inverting them. At least one prior art patent, U.S. Pat. No. 3,670,903 involved a component inverter that pivoted off the floor, with the center of gravity of the component remained over the pivot point. The problem there being that the mass of the component to be flipped had to be shifted perpendicular to the length of the inversion axis in a horizontal direction when the chassis was off the work floor. The horizontal shift would be difficult for a large multi-ton vehicle chassis due to the support requirements during the shift. This patent as well as others in the prior art does not address the application of vehicle chassis manufacture or maintenance. One specific issue with truck chassis inversion is that some vehicle wheelbases, and hence axial weight distributions on the same assembly line may be different. None of the prior art adjusts for vehicle wheel base variations. The problem here is that there may be an uneven load distribution if the separation of support elements cannot be varied. This could result in undesirable shifting of the chassis while elevated.
What is needed and does not exist in the prior art is a chassis inverter and process that uses this inverter that pivots a large chassis from the work floor and does not require horizontal mass shifts while the chassis is in the air and that varies lifting axially locations to account for varying vehicle wheelbases and axial weight distribution.
An object of the invention is to provide is a chassis inverter and process that uses this inverter that pivots a large chassis from the work floor and does not require horizontal mass shifts while the chassis is in the air. An additional object is to provide a chassis inverter that may invert vehicles with varying wheelbases while maintaining even load distribution.
The chassis inverter and process to use the inverter of this invention satisfies these objectives as well as some not mentioned. The chassis inverter consists of a set of clamps that hold the vehicle chassis and a hydraulic driven rotary actuator. The apparatus and an overhead crane system provide a method of inverting and transferring chassis in the short time period needed to meet high volume vehicle manufacturing needs.
The apparatus consists of two c-shaped clamps that cradle the chassis. The clamps are assembled to a shaft may be driven by a hydraulic cylinder through a sprocket and chain arrangement that provides a full 180-degree rotation of the chassis. One clamp may have motorized trolley that provides adjustment needed for handling chassis of widely varying wheelbase.
The process involves an overhead crane system with a bridge crane section may provide the necessary broadside loading motion, and an interlocking monorail section that allows the hoist carriers to exit the bridge and travel perpendicularly to the inverting apparatus"" loading direction. The chassis is then transferred to a next assembly conveyer.
Additional effects, features and advantages will be apparent in the written description that follows.